Online Education and Undergraduates' Academic Record during the COVID-19 Pandemic in China: Evidence from Large-Scale Data

Digital technology-based online education is key to promoting high-quality development of higher education. Many studies have analyzed the effects of online education during the COVID-19 pandemic, but analyses based on large-scale data are lacking. This study uses a quasi-natural experiment during the COVID-19 pandemic to explore the short- and long-term relationships between emergency remote education (teaching and learning) and undergraduates' academic record using multiple comparison analysis of variance (ANOVA) and multiple linear regression. The research data come from the academic record of 123,208 courses of 2622 undergraduates from the classes of 2017–2021 in a Chinese university, across nine semesters. The data do not satisfy the homogeneity of variance hypothesis test;therefore, a non-parametric test is adopted for hypothesis testing. The results show that: (1) In the online education semester, the students' academic record improved substantially with low fluctuation and greater stability;(2) this improvement is more obvious for sophomores and juniors than for freshmen, and (3) online education during the pandemic period significantly improved the course scores of undergraduates, especially sophomores, in the following one or two semesters.

mRNA vaccines in the prevention and treatment of diseases.

Messenger ribonucleic acid (mRNA) vaccines made their successful public debut in the effort against the COVID-19 outbreak starting in late 2019, although the history of mRNA vaccines can be traced back decades. This review provides an overview to discuss the historical course and present situation of mRNA vaccine development in addition to some basic concepts that underly mRNA vaccines. We discuss the general preparation and manufacturing of mRNA vaccines and also discuss the scientific advances in the in vivo delivery system and evaluate popular approaches (i.e., lipid nanoparticle and protamine) in detail. Next, we highlight the clinical value of mRNA vaccines as potent candidates for therapeutic treatment and discuss clinical progress in the treatment of cancer and coronavirus disease 2019. Data suggest that mRNA vaccines, with several prominent advantages, have achieved encouraging results and increasing attention due to tremendous potential in disease management. Finally, we suggest some potential directions worthy of further investigation and optimization. In addition to basic research, studies that help to facilitate storage and transportation will be indispensable for practical applications.

Insight into the origin of SARS-CoV-2 through structural analysis of receptor recognition: a molecular simulation study† † Electronic supplementary information (ESI) available. See DOI: 10.1039/d1ra00127b

Bats and pangolins are considered to be potential hosts of the new coronavirus SARS-CoV-2, based on its genome similarity to coronaviruses of these species (Bat-CoV-RaTG13 and Pangolin-CoV). The receptor-binding domain (RBD), a functional component of the spike protein, is responsible for binding of SARS-CoV-2 by human ACE2 receptors and is also key to cross-species viral transmission. We performed molecular dynamics (MD) simulations using structures of hACE2 in complex with the RBD of SARS-CoV-2, SARS-CoV, Pangolin-CoV and Bat-CoV-RaTG13, respectively. By analyzing the hydrogen-bonding network at the RBD–hACE2 interface and estimating the binding free energies between RBD and hACE2, we found Pangolin-CoV bound hACE2 in a similar state as did SARS-CoV-2, and both of them bound hACE2 more strongly than did Bat-CoV-RaTG13 or SARS-CoV. We further identified two major adaptation mutations of SARS-CoV-2-RBD, which may have significant roles in regulating the recognition and binding between RBD and hACE2. Our results add to existing evidence that Pangolins have the potential to act as an intermediate host for SARS-CoV-2, and provide guidance for future design of antiviral drugs and vaccines. The origin of SARS-CoV-2 through structural analysis of receptor recognition was investigated by molecular dynamics simulations.

A Review: The Manifestations, Mechanisms, and Treatments of Musculoskeletal Pain in Patients With COVID-19.

The outbreak of COVID-19 poses a serious threat to global health. Musculoskeletal (MSK) pain is the most frequent symptom in patients with COVID-19 besides fever and cough. There are limited studies addressing MSK symptoms in patients with COVID-19. This review aims to provide an overview of current studies related to MSK pain in patients with COVID-19, summarize the possible mechanisms of myalgia, and describe the current management options. In addition to acute respiratory manifestations, COVID-19 might also affect neurological systems which include skeletal manifestations and muscular injury. A possible mechanism of MSK pain and myalgia in COVID-19 may be related to the distribution of angiotensin-converting enzyme 2 (ACE-2) and the occurrence of cytokine storms. ACE-2 has been shown to be the receptor of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-COV2). Moreover, studies have shown that inflammatory cytokines could cause myalgia by inducing prostaglandin E2 (PGE2) production. In addition, it was also found that the plasma levels of IL2, IL7, IL10, IL-6, TNFα, and e lymphopenia were higher in patients with COVID-19. In general, the treatment of MSK pain in patients with COVID-19 falls into pharmacological and non-pharmacological interventions. Various treatments of each have its own merits. The role of vaccination is irreplaceable in the efforts to prevent COVID-19 and mitigates its subsequent symptoms.

Development and Validation of a Nomogram to Assist Monitoring Nosocomial SARS-CoV-2 Infection of Hospitalized Patients.

PURPOSE: SARS-CoV-2 is extremely infectious, and the incidence of nosocomial infection is conceivably high. We aimed to develop and validate a nomogram to assist monitoring nosocomial SARS-CoV-2 infection in hospitalized patients. PATIENTS AND METHODS: There were 437 COVID-19 hospitalized cases and 420 negative inpatients enrolled from two hospitals in Hubei province, China. We compared the demographic and clinical characteristics of participants between the two groups. Then, LASSO regression and logistic regression were applied to build a nomogram for SARS-CoV-2 infection prediction in the development cohort. Our nomogram was assessed by area under the curve (AUC), calibration curve, decision curve (DCA) and clinical impact curve analysis (CICA). RESULTS: After LASSO regression filtration, eleven laboratory indicators were correlated with SARS-CoV-2 infection. Then, we integrated these features and constructed a nomogram, which showed a high AUC 0.863 (95% CI: 0.834-0.892) in the development cohort with a sensitivity of 80.41% and specificity of 77.38% and 0.813 (95% CI: 0.760-0.866) in validation cohort with a sensitivity of 82.98% and specificity of 70.43%. The calibration plot displayed that the predicted outcomes were in good concordance with the actual observations. DCA and CICA further showed a larger clinical net benefit. CONCLUSION: We constructed and validated a nomogram that integrated eleven laboratory indexes to assist monitoring of nosocomial SARS-CoV-2 infection in hospitalized patients. Our nomogram is remarkably informative for clinical practice, which will be helpful for preventing SARS-CoV-2 further transmission in hospital and avoiding nosocomial infection.

Bhimamycin J, a Rare Benzo[f]isoindole-dione Alkaloid from the Marine-Derived Actinomycete Streptomyces sp. MS180069.

Chemical investigation on a Streptomyces sp. strain MS180069 isolated from a sediment sample collected from the South China Sea, yielded the new benzo[f]isoindole-dione alkaloid, bhimamycin J (1). The structure was determined by extensive spectroscopic analysis, including HRMS, 1D, 2D NMR, and X-ray diffraction techniques. A molecular docking study revealed 1 as a new molecular motif that binds with human angiotensin converting enzyme2 (ACE2), recently described as the cell surface receptor responsible for uptake of 2019-CoV-2. Using enzyme assays we confirm that 1 inhibits human ACE2 79.7 % at 25 µg/mL.

Engaging readers across participants: A cross-interactant analysis of metadiscourse in letters of advice during the COVID-19 pandemic

Reader engagement has often been explored from a metadiscourse perspective, but little research has been conducted on the variation in engagement across participants, especially readers. Based on data from a collection of 120 Chinese letters of advice from governments and hospitals produced during the COVID-19 pandemic, a cross-interactant analysis of metadiscourse is conducted in this paper, and the interactants’ impacts on reader engagement are discussed. The findings reveal that (1) both governments and hospitals utilize engagement markers, boosters, attitude markers, and frame markers more than other types of metadiscourse items;(2) differences exist in the use of metadiscourse among the issuing agencies;(3) as reader identity varies from ingroup to outgroup membership, the probability of booster use by a hospital is higher than that by a government;and (4) the likelihood of using frame, transition and attitude markers is higher for governments than for hospitals. The paper concludes by discussing different communicative styles adopted by two agencies in a crisis context.

A fully automated microfluidic PCR-array system for rapid detection of multiple respiratory tract infection pathogens.

Rapid and accurate identification of respiratory tract infection pathogens is of utmost importance for clinical diagnosis and treatment, as well as prevention of pathogen transmission. To meet this demand, a microfluidic chip-based PCR-array system, Onestart, was developed. The Onestart system uses a microfluidic chip packaged with all the reagents required, and the waste liquid is also collected and stored on the chip. This ready-to-use system can complete the detection of 21 pathogens in a fully integrated manner, with sample lysis, nucleic acid extraction/purification, and real-time PCR sequentially implemented on the same chip. The entire analysis process is completed within 1.5 h, and the system automatically generates a test report. The lower limit-of-detection (LOD) of the Onestart assay was determined to be 1.0 × 103 copies·mL-1. The inter-batch variation of cycle threshold (Ct) values ranged from 0.08% to 0.69%, and the intra-batch variation ranged from 0.9% to 2.66%. Analytical results of the reference sample mix showed a 100% specificity of the Onestart assay. The analysis of batched clinical samples showed consistency of the Onestart assay with real-time PCR. With its ability to provide rapid, sensitive, and specific detection of respiratory tract infection pathogens, application of the Onestart system will facilitate timely clinical management of respiratory tract infections and effective prevention of pathogen transmission. Onestart, a ready-to-use system, can detect 21 pathogens in a fully integrated manner on a microchip within 1.5 h.

Insight into the origin of SARS-CoV-2 through structural analysis of receptor recognition: a molecular simulation study.

Bats and pangolins are considered to be potential hosts of the new coronavirus SARS-CoV-2, based on its genome similarity to coronaviruses of these species (Bat-CoV-RaTG13 and Pangolin-CoV). The receptor-binding domain (RBD), a functional component of the spike protein, is responsible for binding of SARS-CoV-2 by human ACE2 receptors and is also key to cross-species viral transmission. We performed molecular dynamics (MD) simulations using structures of hACE2 in complex with the RBD of SARS-CoV-2, SARS-CoV, Pangolin-CoV and Bat-CoV-RaTG13, respectively. By analyzing the hydrogen-bonding network at the RBD-hACE2 interface and estimating the binding free energies between RBD and hACE2, we found Pangolin-CoV bound hACE2 in a similar state as did SARS-CoV-2, and both of them bound hACE2 more strongly than did Bat-CoV-RaTG13 or SARS-CoV. We further identified two major adaptation mutations of SARS-CoV-2-RBD, which may have significant roles in regulating the recognition and binding between RBD and hACE2. Our results add to existing evidence that Pangolins have the potential to act as an intermediate host for SARS-CoV-2, and provide guidance for future design of antiviral drugs and vaccines.

Techniques and Strategies for Potential Protein Target Discovery and Active Pharmaceutical Molecule Screening in a Pandemic.

Viruses remain a major challenge in the fierce fight against diseases. There have been many pandemics caused by various viruses throughout the world over the years. Recently, the global outbreak of COVID-19 has had a catastrophic impact on human health and the world economy. Antiviral drug treatment has become another essential means to overcome pandemics in addition to vaccine development. How to quickly find effective drugs that can control the development of a pandemic is a hot issue that still needs to be resolved in medical research today. To accelerate the development of drugs, it is necessary to target the key target proteins in the development of the pandemic, screen active molecules, and develop reliable methods for the identification and characterization of target proteins based on the active ingredients of drugs. This article discusses key target proteins and their biological mechanisms in the progression of COVID-19 and other major epidemics. We propose a model based on these foundations, which includes identifying potential core targets, screening potential active molecules of core targets, and verifying active molecules. This article summarizes the related innovative technologies and methods. We hope to provide a reference for the screening of drugs related to pandemics and the development of new drugs.

Synchronous distance education vs traditional education for health science students: A systematic review and meta-analysis.

CONTEXT: Synchronous distance education (SDE) has been widely used for health science students in recent years. This study examined the effectiveness and acceptance of SDE compared with traditional education for health science students and explored the potential moderators that could impact the pooled results. METHODS: A systematic review and meta-analysis was conducted of randomised controlled trials (RCTs) from January 2000 to March 2020 searched on nine electronic databases, including Web of Science, PubMed, Cochrane Library, Scopus, EMBASE, CINAHL, ERIC, PsycINFO, and ProQuest Dissertations and Theses. The outcomes measured were knowledge, skills with objective assessments and overall satisfaction with subjective evaluations. The pooled results were calculated using random-model effects, and moderators were explored through meta-regression. RESULTS: A total of seven RCTs with 594 participants were included. At the post-test level, the pooled effect size of knowledge acquisitions (SMD 0.12, 95% CI -0.07-0.32) showed insignificant difference between the SDE and traditional education groups (P = .207), with low heterogeneity (I2  = 17.6%). Subgroup analyses observed no factors that significantly impacted the pooled results of knowledge acquisition at the post-test levels (P for interaction > 0.05). Knowledge gains from pretest to post-test in SDE groups also did not differ significantly between groups (SMD 0.15, 95% CI -0.22-0.53; P = .428). The pooled effect size of skills (SMD 0.02, 95% CI -0.24-0.28; P = .735) was similarly insignificant. The pooled effect size of overall satisfaction (SMD 0.60, 95% CI 0.38-0.83; P < .001) significantly favoured SDE over traditional education. Incorporating two-group studies without randomisations did not significantly change the overall results of knowledge acquisition at the post-test level (SMD -0.002, 95% CI -0.11-0.10; P = .994), with moderate heterogeneity (I2  = 61.9%). CONCLUSIONS: Synchronous distance education was not significantly different from traditional education in effectiveness and had higher satisfaction ratings. Our findings might provide indications for adoptions of online remote education in health science education centres.

Dynamic changes of throat swabs RNA and serum antibodies for SARS-CoV-2 and their diagnostic performances in patients with COVID-19.

Dynamic changes of RNA and antibodies in SARS-CoV-2 infected patients remain largely unknown, and influence factors for antibody production have not been fully clarified. In this study, consecutive throat swabs specimens (n = 1875) from 187 patients were collected to analyse the dynamic changes of RNA. Moreover, 162 serial serum samples from 31 patients were tested for seroconversion of IgM and IgG. Meanwhile, IgM and IgG were also detected in 409 COVID-19 patients and 389 controls. Additionally, the logistic regression analysis was executed to identify the possible influence factors for antibody production. The median positive conversion time for RNA was day 7 (IQR, 3-11), and the positive rate was highest in day 1-5 (74.59 %) and then gradually decreased. The median time of seroconversion for IgM and IgG were both day 12 (IQR, 10-15). The sensitivity and specificity for IgM (or IgG) was 87.04% and 96.92%, respectively. Multivariate logistic regression indicated that reduced lymphocytes and short positive conversion time for SARS-CoV-2 RNA were independent factors for negative results of IgM and IgG. In conclusion, RNA and antibodies should be combined for COVID-19 diagnosis, and delayed seroconversion was influenced by the decreased lymphocytes and short positive conversion time for RNA.